Tropical Storm Nesat Develops near Northern Luzon

Tropical Storm Nesat developed over the Western North Pacific Ocean near northern Luzon on Saturday morning. At 5:00 a.m. EDT on Saturday the center of Tropical Storm Nesat was located at latitude 18.6°N and longitude 123.5°E which put it about 160 miles (260 km) east of Claveria, Philippines. Nesat was moving toward the west at 25 m.p.h. (40 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1000 mb.

The circulation around a low pressure system over the Western North Pacific Ocean near northern Luzon strengthened on Saturday morning and the Japan Meteorological Agency designated the system as Tropical Storm Nesat. The distribution of thunderstorms in Tropical Storm Nesat was asymmetrical. Many of the thunderstorms were occurring in bands in the western half of Nesat’s circulation. Bands in the eastern side of Tropical Storm Nesat consisted primarily of showers and lower clouds. Storms near the center of Nesat generated upper level divergence that pumped mass away to the west of the tropical storm. Winds to tropical storm force extended out 125 miles (200 km) in the northern side of Nesat’s circulation. The winds in the southern half of the circulation were blowing at less than tropical storm force.

Tropical Storm Nesat will move through an environment favorable for intensification during the next 36 hours. Nesat will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the southern part of an upper level ridge over the Western North Pacific Ocean. The ridge will produce easterly winds that will cause some vertical wind shear. The wind shear will inhibit intensification, but Tropical Storm Nesat is likely to strengthen during the next 36 hours. Nesat could intensify to a typhoon by the end of the weekend.

Tropical Storm Nesat will move around the southern side of a surface high pressure system over the Western North Pacific Ocean. The high pressure system will steer Nesat toward the west during the next 36 hours. On its anticipated track, Tropical Storm Nesat will pass near northern Luzon during the next 24 hours. Nesat will bring gusty winds and locally heavy rain to northern Luzon. Heavy rain could cause flash floods in some locations. Tropical Storm Nesat will move over the South China Sea on Sunday.